FA

Ver. 2.3.15 Build 15.04.2014

FA running on server:
Versión Apache    2.2.29
Versión PHP    5.4.35
Versión MySQL    5.5.42-cll
Arquitectura    x86_64
Sistema operativo    linux

I am using a MacBook Pro - Yosemite 10.10.2
Google Chrome ver. 41

but It fails also from Windows - Explorer or Chrome

Dear All:

I am getting this answer when I try to do anything in FA. I have to unable Javascript.

The thing is that this changes from one day (that everything works) to another where nothings seems to work.

I get always the error:
JsHttpRequest: JavaScript code generated by backend is invalid!

when I try to order the providers, try to choose in combobox... everywhere...

Anyone have any idea??? thank you